1612.18 liters of oil were in the container first
Step-by-step explanation:
Volume of oil in the container=x
Total volume of oil in the bottle and the container=2015 L
Volume of the oil in the bottle=2015-x
When 0.18L oil was poured from the container to the bottle
New volume in the container=x-0.18
New volume in the bottle=2015-x+0.18
New volume in the container is 4 times the oil that was in the bottle
Hence x-0.18=4(2015-x+0.18)
x-0.18=8060-4x+0.72
x=1612.18